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Hi all, just a few points on this discussion. Everyone talks about a 6v system when in fact it is more like 7.2 volts. I understand that the a/c clutch is for a 12v system and not being electronic it should and will work well below the 13.6 v of a 12 v system.
I suggest that the clutch will work on a 6v system and will work well so long as the battery is up to speed, say at around 7 volts. The only time that it may slip is ona stinking hot day at the traffic lights when the voltage regulator has not cut in and the battery voltage drops below say 6.75 volts.
The clutch is not electronic and it will try to engage at a low voltage, there may just be some slippage at lower voltages, but I suggest it will not be noticeable.
I run 7.6 volts instead of 7.4 volts on my 6v vehicles to get a higher initial charging rate and it may mean that the battery lasts 7.5 years instead of 8 years, but it is a small price to pay.
In summary....I believe that a good 6v system will operate the 12 v a/c clutch satisfactorily.

Best regards Peter Toet

I personally rule out the 8 volt battery option.

It ends up making the system odd-ball.

I am aware the light bulbs are usually labeled 6 - 8 volt, but the higher voltage the shorter the life of an incandescent bulb. Same problem with radio tubes which are designed for a 6.3 volt filament.

I don't know how the gauges work with the higher voltage, I know they talk about voltage regulator devices in the service manual but I have never explored to find out how they actually regulate (iron wire ballast?)


Jim

I think the consensus is the clutch will work on 6v which leaves the blower as the villain.

Since there doesn't appear to be a dual shaft 6v motor easily available, one would have to figure how to make a single shaft motor work two wheels or change the evaporator to a single blower setup.

A suggestion was made to run a 12v blower on 6v. This might work on the two wire motors which use a rheostat. The downside would be the blowers fastest speed would be equivalent to a low speed or whatever RPM 6v would produce & the low or medium settings would probably be nonexistent. That approach might not work well for the times higher speeds would be desirable. If the motor was the newer type with multiple taps or multiple field windings, only one at a time being selected for a particular speed, I'd be concerned trying to run on 6v wouldn't be a good idea -- if it worked at all.

Quote:

The stock Packard (King-Seeley) instrument regulator is a thermal bimetal type. It uses the supply voltage to heat a bimetal strip which opens and closes a set of contacts. The full supply voltage is turned on and off with a cycle depending on the supply voltage and load. The resultant output is effectively chopped supply voltage. Since the instruments are also thermal, the on/off cycle happens so rapidly the instruments don't have time to respond & the chopping action is not seen.

Just for grins, here is the internals of a regulator and the 12v output waveform.

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Let us consider a smallest common ordinary PASSENGER CAR battery. Altho in recent years nolonger specified is something called and AMP-HOUR rating. I belive such a specification is general to ANY battery.

IF the amp-hour rating of a battery is say 200 amp-hours then that means 200 amps for one hour or 1 amp for 200 hours before it is completely discharged.

So if a 12v clutch and blower motor is demanding say 10 amps and a 200 amp-hour battery is used then at least 10 hours of operation would be had from the system before the battery would have to be recharged.

However, i do not know what the amp-hour rating of a usual normal run of the mill common garden variety passenger car battery actual is. I'm guessing about 200 amphours. At least 100.

For 200 Ah (C/20) you are looking at a high capacity marine deep cycle battery. I'd be surprised to find a 100 Ah starting battery. That kind of capacity is just not needed for a short, high amp draw application. What is needed for starting is a battery that can dump a lot of electrons very quickly.

Ok then. A 200 Ah (C/20) high capacity marine deep cycle battery. Mount one somewhere on the car. Wire it to the 12v AC clutch and fan blower. No other additional bits and pieces needed. Just have to recahrge the battery with a battery charger every what??? Every 10 to 15 hours of use????

Maybe not good for long distance touring of over 400 miles across 3 or 4 days but for one or two days of touring would it not work just fine????

This is all valuable discussion and don't take me as argumentative.

The regulator looks simple and low cost (thanks for the picture); I'm surprised the contact points would go the life of these cars. I do recall seeing several in the dash board circuit. I haven't pulled my instrument panel yet but soon, as I am going to fix my clock.

I am going to try the compressor clutch on 6 volts and see how it works. It seems possible a guy could rewind the clutch coil for 6 volts if he knew what he was doing.

When I run the A/C it is hotter than the hubs of Hell here in Phoenix
AZ. This is among the reasons I don't want to jack up the charge voltage as we figure two years to cook a battery here.

The fan motor could be run on 6 volts easily and just leave the fan speed on high. I hate the noise it makes anyway. I thought possibly a guy could rewind the fan motor with less turns of heavier wire, there isn't much to them in the first place. It would run backwards on positive ground as I believe these motors are permanent magnet type. I believe the squirrel cages are the same size so switch them end to end.

The control module may have electronic parts and it would need to be connected to the proper polarity. So Far I haven't got it cold enough to let the clutch drop out anyway.

A couple of times I thought of taking the system out completely but then July comes around.

My 6 Volt Optima battery is rated at close to 1000 CCA and it cranks the car without hesitation and eats half the shelf space.

My 12 volt alternator will keep up with the load as long as the car is going down the road but just barely.


jIM